<?php
/*
 * MiniMe - a minimalistic OStatus complient microblogging tool
 * Copyright (C) 2010, Tuomas Koski - koski.tuomas@gmail.com
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * This class is representing a XML feed similar to this:
 * <title>My timeline!</title>
 * 
 * @author     Tuomas Koski <koski.tuomas@gmail.com>
 * @copyright  Tuomas Koski
 * @license    http://www.gnu.org/licenses/lgpl.txt
 */
class Atom_Feed_Subtitle implements Atom_ChildElement {
    
    private $subtitle;
    
    const ELEMENT_SUBTITLE = "subtitle";
    
    public function __construct($subtitle) {
        $this->setSubtitle($subtitle);
    }
    
    private function setSubtitle($subtitle) {
        if(empty($subtitle)) {
            throw new Exception("Subtitle cannot be set empty.");
        }
        $this->subtitle = $subtitle;
    }
    
    public function getSubtitle() {
        return $this->subtitle;
    }
    
	/**
     * @return DOMElement
     */
    public function asDomElement(DOMDocument $dom) {
        return $dom->createElement(self::ELEMENT_SUBTITLE, $this->subtitle);
    }
    
    /**
     * @param DOMElement $elm
     * @return Atom_Feed_Subtitle
     */
    public static function buildFromDOMElement(DOMElement $elm) {
        return new Atom_Feed_Subtitle($elm->nodeValue);
    }
}